Duct with paint sealant

ABSTRACT

An HVAC component and method of forming the HVAC component, including a duct having a first surface and a second surface movable between an unassembled position and an assembled position is provided, wherein the method includes (a) applying a paint sealant to one of the first and the second surfaces; (b) one of drying or curing the applied paint sealant; and (c) moving the first and second surfaces from the unassembled to the assembled position, the paint sealant forming a sealed interface between the assembled first surface and second surface.

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure generally relates sealing ductwork andparticularly to a paint sealant for sealing ductwork, such as HVACducts.

Description of Related Art

Round snaplock pipe and associated fittings are used within residentialHVAC systems and the low pressure portions of commercial and industrialHVAC systems. It is advantageous for many reasons that the system beleak free.

It is common in the HVAC industry to install the HVAC system and afterinstallation attempt to seal all joints and seams as well as anypotential voids that offer the opportunity for leaks in the system bypainting the system with a duct sealant to seal said air leaks. Thisprocess is time consuming, difficult and often ineffective due to theductwork being located high in the air, within concealed spaces orimmediately adjacent to other building components.

Recent technological advances have led to the development of sealedsnaplock pipe that does not require the application of duct sealantafter installation. Examples of sealant being used on snaplock pipe canbe seen in U.S. Pat. Nos. 7,478,467, 7,708,034 and 8,151,430. However,these patents rely upon the accurate insertion of liquid appliedgasketing sealant that hardens to occupy a substantial portion of thelock mechanism.

Existing duct sealants:

1. are messy and time consuming in application and the duct sealant mustbe allowed to dry for an extended time prior to shipping orinstallation;

2. result in sealant and brush marks on the fitting or snap lockmechanism which are not as aesthetically pleasing as the remainder ofthe system without duct sealant; and

3. application of the duct sealant to the interior of the fitting wouldbe time consuming, likely ineffective due to the size of the fittingsand not desirable due to the potential for fumes and odors that may beintroduced to the conditioned air.

Therefore, the need exists for an HVAC component, including ducts,having a confronting, abutting or joined surfaces that has a paintsealant located to form a substantially sealed interface of the surfacesconfronting, abutting or joining.

BRIEF SUMMARY OF THE INVENTION

The present method provides forming a duct component having a firstsurface and a second surface movable between an unassembled position andan assembled position, the method including the steps of applying apaint sealant to one of the first and the second surfaces; one of dryingor curing the applied paint sealant; and moving the first and secondsurfaces from the unassembled to the assembled position, the paintsealant forming a sealed interface between the assembled first surfaceand second surface. The method can include applying the paint sealant bya transfer roller. The method can also include exposing the paintsealant to a predetermined radiation or heat to cure the paint sealant.It is also contemplated the paint sealant can be applied by spraying thepaint sealant onto the one of the first and the second surface.

The present disclosure provides a duct component having a first surfaceand a second surface movable between an unassembled position and anassembled position; and a paint sealant on one of the first and thesecond surfaces, the paint sealant being one of dried or cured. Thepaint sealant can be rubberized or include any of a thermoplastic,thermoset, thermoplastic elastomer or elastomer.

Alternatively, a duct component is provided having a paint sealant on aportion of the duct component, the paint sealant being one of dried orcured.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a cross sectional view of a snap lock mechanism in anunassembled or unlocked configuration.

FIG. 2 is a cross sectional view of the snap lock mechanism of FIG. 1 inan assembled or locked configuration.

FIG. 3 is a cross sectional view of an alternative snap lock mechanismwith confronting surfaces in an unassembled or unlocked configuration,showing the location of the paint sealant.

FIG. 4 is a cross sectional view of a further alternative snap lockmechanism with confronting surfaces in an unassembled or unlockedconfiguration, showing the location of the paint sealant.

FIG. 5 is a cross sectional view of another alternative snap lockmechanism with confronting surfaces in an unassembled or unlockedconfiguration, showing the location of the paint sealant.

FIG. 6 is a cross sectional view of an additional alternative snap lockmechanism with confronting surfaces in an unassembled or unlockedconfiguration, showing the location of the paint sealant.

FIG. 7 is a schematic representation of the application of the paintsealant to a portion of a duct or fitting.

FIG. 8 is a schematic representation of an alternative application ofthe paint sealant to a portion of a duct or fitting.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1-6, the present system provides an HVAC product,such as a duct or fitting component that can be manufactured, stored,shipped and subsequently assembled to an air tight configuration withoutrequiring the subsequent or on-site application of a sealant.

The term air tight encompasses industry standards for leakage at a givenpressure (positive or negative).

The HVAC product can be any of a variety of components that can have anunassembled and an assembled configuration. The unassembled andassembled configurations encompass components that have confronting,abutting or joinable surfaces. The surfaces can be retained bymechanical interlock, fasteners, deformation or adhesives.

Further, the confronting surfaces can be in a longitudinal seam have alocking mechanism or self locking mechanism that allows two edges ofsheet metal to be joined together without a separate fastener to form aduct. These longitudinal seams can be any of a variety of configurationsincluding button lock and a reeves lock.

Representative confronting surfaces include those snap lock profilesshown in FIGS. 1 and 2 as well as those disclosed by Sheet Metal and AirConditioning Contractors National Association (SMACNA), shown in FIGS.3-6.

FIG. 1 shows the profile of a sheet metal duct 10 having a disengagedlocking mechanism 20 in the configuration of a button lock. The lockingmechanism 20 includes a female portion 30 and a male portion 40. Thelocking mechanism 20 can be a self locking mechanism, such as a buttonlock which includes a button 32 on female portion 30. If the button 32were not formed in the locking mechanism, the locking mechanism would bein the form of a reeves lock.

As seen in the Figures, the female portion 30 defines a socket having awidth W for receiving the male portion 40. For each locking mechanism,the width W has a given dimension.

A paint sealant 50 is located on a portion of at least one of the femaleportion 30 and the male portion 40. Although shown in the Figures onmultiple surfaces of each of the female portion 30 and the male portion40, the locations are illustrative as the specific location is at leastpartially dictated by the specific locking mechanism, the tolerances inthe locking mechanism, the layers of paint sealant used and the desiredresistance to leakage.

The paint sealant 50 has a viscosity between approximately 320 CPS(centipoise) to 100,000 CPS, with a preferred range of approximately 500CPS to 20,000 CPS. Upon curing or drying, the paint sealant is nottacky, does not string and does not run or drip from the appliedlocation on the lock mechanism 20.

In FIG. 2, the locking mechanism 20 of FIG. 1 is shown in the engaged orassembled configuration, wherein the male portion 40 is engaged with thefemale portion 30. The paint sealant 50 prevents air from escapingthrough the locking mechanism 20. In selected applications of the paintsealant 50, the sealant can be encapsulated by the sheet metal duct whenthe self locking mechanism 20 is in the assembled state. Sufficientpaint sealant 50 can be applied to create a snug or tight fit betweenfemale portion 30 and male portion 40 which results in an improvedconnection for the locking mechanism 20. That is, reducing the availableplay or relative movement between the confronting surfaces, reduces thevibrational sounds generated by the duct (or fitting) during operation.

Further, by providing a compressible interface between the confrontingsurfaces, the paint sealant 50 can accommodate the expansion andcontraction of the duct upon the passage of different temperature air.

The paint sealant 50 occupies less than 50% of the width W of the femaleportion 30, and in select configurations less than 30% and depending ofthe configuration of the lock mechanism, less than 10% to less than 5%.As the paint sealant 50 represents less material than the prior systems,the paint sealant provides increased manufacturing efficiencies.

Further, as the paint sealant 50 occupies less than 50% of the width W,and as little as 5%, the locking mechanism 20 can accommodate variationsin the amount of paint sealant in the mechanism and maintain an operableinterconnection.

That is, in contrast to prior systems in which it is critical to get acorrect amount of sealant in the locking mechanism (too much may notcause the locking mechanism to not engage and too little will cause thelocking mechanism to not seal properly), the present paint sealant 50increases the working range of the locking mechanism with respect to thesealant.

In view of modern manufacturing capabilities, the HVAC components can bemanufactured wherein the tolerances provide for gaps or interfacespacing that are preferably less than 0.25 inch, and more preferablyless than 0.125 inch and most preferably less than 0.0625 inch.Depending on the specific manufacturing line, the tolerances may resultin gap sizing that is approximately 0.0313 inches.

As current tolerances are much tighter on HVAC products because ofimproved manufacturing methods, the gaps in seams are much tighter andrequire much less sealing materials to seal. Therefore, the presentdisclosure provides a relatively thick paint with sealing propertieswhich may be ideal for seal formation and be much more cost effectiveand practicable as compared to the Ductmate GreenSeam™ products, andHard Cast products or equivalents. The paint sealant 50 can also beapplied via a transfer method, such as brush or roller as opposed toinjection or extrusion.

Representative paint sealants 50 include Performix Brand Plasti DipBlack Rubber Coating; LOCTITE Rubber Protectant Color Guard, CRCUrethane Seal Coat Coating, BEHR Elastomeric Paint (or Sherwin Williamsor Benjamin Moore) as well as Hyperflex Primer—Series 304. The paintsealant is not a paint, as the material must not only withstand theapplicable fire safety codes, but the material must also provide forsealing to air tight as well accommodating compressive forces of theassembled confronting surfaces.

Elastomeric paints can be employed as the paint sealant 50. Elastomericpaints provides a waterproof paint coating that is resistant to heat,cold, sunlight, and rain. Elastomeric paint has very good elongationcharacteristics which can accommodate expansions and contracts of theduct.

It is contemplated the elastomeric paints can be employed in one or twocoats applications. The elastomeric paints can be applied by a roller,brush, or airless paint sprayer. Typical sprayer outputs are on theorder of 1 gal per min with a spray pump. An acrylic binder can be addedto the elastomeric paint prior to application.

Elastomeric paints and hence coatings can have more than 4 times thethickness of commercially available latex paint. The elastomeric paintscan also contain mildewcide that prevents mildew growth on damp areas.

In select configurations, the paint sealant 50 can have a specificgravity between 0.5 and 1 with an approximately weight of 5.5 pounds pergallon.

Thus, an appropriate paint sealant 50 can be selected and applied in amethod that is unique to HVAC components and much less expensive, andcompete with the current methods on the market.

In selected configurations, the paint sealant 50 provides at leastexceed 2″ w.c. of pressure and is capable of much higher pressures withminimal leakage, such as 10 inches water column. The paint sealant 50can provide leakage rates at 2″ w.c. or less of less than 0.1 cfm perlinear foot for longitudinally sealed duct.

The paint sealant 50 can include additives to prevent mold or fungus, orprovide different colors, or heat resistant additives can beincorporated for high temperature applications. Therefore, the paintsealant 50 has a broad market application in HVAC and flue venting ofexhaust gases.

The present system includes a method of forming a sealed pipe or duct bylocating a paint sealant 50 on a predetermined portion of the duct, suchthat when the duct is assembled, the previously applied paint sealantcontacts an opposing portion of the duct (or an opposing confrontingsurface having the paint sealant) and forms an at least substantiallysealed interface. Thus, as seen in FIGS. 7 and 8, one could use a paintproduct (paint sealant), and spray or transfer the paint sealant along amale lock or a female lock, on rectangular or round residential, orcommercial HVAC duct fabricated out of CRS or aluminum, coated withgalvanized, PVC, oil or water based paint products, high temperatureresistant paint, aluminum, or any other variety or combination of thesecoatings.

Additionally, the paint sealant 50 could be applied on overlappingjoints or seams interlocking or riveted or dimpled, of round to round,or round to oval, or round to square or rectangular, or any othercombination of these duct transitions. The sealed ducts could be used inconditioned (chilled or heated or humidified or dehumidified air) forcedair, negative or positive air pressure HVAC residential and commercialsystems.

The paint sealant 50 is applied during the manufacturing of the ductproducts at a manufacture's facility. The paint sealant can be sprayedon, or applied as a transfer paint process, as shown in FIGS. 7 and 8.The paint sealant 50 could be applied in one layer, or several layersdepending on the desired seal thickness or requirement. As seen in FIG.7, rollers 60 transfer the paint sealant from a reservoir to the HVACcomponent. The paint sealant 50 could be applied along any lateral,longitudinal, overlapping seam or interlocking seam, partially assembledor fully assembled, or un-assembled and shipped directly from the pointof manufacture in an assembled or unassembled configuration. Heated orforced air could be used to aid in the drying or curing of the paintsealant during application in production machinery that runs at highspeed, thereby reducing the drying or curing time to aid in fastermanufacturing, packaging and handling of the paint sealed product.

This paint sealant 50 may not be technically considered paint but forthe purpose of this description it is set forth as a paint or paintsealant. The paint sealant encompasses a rubberized oil based paintproduct, which can dry or cure, wherein the curing can be by agents suchas ambient moisture, or by activations such as heat or radiation. Thatis, the paint sealant is curable. Alternative configurations of thepaint sealant include thermoplastics, thermosets and elastomers, such aspolyethylene, polypropylene, ABS, acrylics, polystyrene, polyester,polyurethane, nylon, polysulfone, polycarbonate, polyvinyl chloride,thermoplastic vulcanizates, urethane, styrene, polyamide andthermoplastic polyolefin.

The paint sealant 50 can be applied in a variety of thicknessesdepending on the joints requiring a seal (one transfer paint roll afteranother, or several spray heads, as seen in FIG. 8, mounted one afteranother in series along the manufacturing line, to build up asufficiently thick layer of paint sealant, thus controlling thethickness desired).

Typical thickness for the paint sealant can range from 2 mils (50.8microns) to 31 mils to 62 mils to typically less than 125 mils.

The paint sealant 50 can be tinted a variety of colors based onapplication needs, and temperature requirements, or humidityrequirements, such as tinted black and have metallic additives andapplied to Gray Metal's black stove pipe and stove pipe fittings thatare exposed to high (100° F.-1,000° F.) temperature flue gases. Thepaint sealant, with any desired coloring, could also be applied to othercolors of wood stove flue pipe, such as but not limited to red, green,blue, or brown. The paint sealant could be applied on the smallreceiving end of pipe, elbows, or fittings of any configuration (round,oval, square, rectangular), and could also be applied on the large endof those same products; it would have no limits on what seams it couldbe applied to or joints, or joining surfaces. The paint sealant 50 couldalso be applied to any fixture or fastener such as an S-Cleat used tojoin or aid in the joining of segments one to another of an HVAC system.Different additives could be added into the paint sealant 50 to increasesealing properties (such as maintain single use or re-sealable use, ormake the paint sealant more suitable for different needs such as coolhumid environments, or hot dry environments, or high heat in excess of100° F., or a combination of any of these possible environments.

The paint sealant 50 provides for the creation of a complete pre-sealedHVAC duct (residential or commercial) system direct from themanufacturer that eliminates the need for the end user to apply mastic,or duct tape, to improve the efficiency of the HVAC system by reducingor eliminating air leaks into, or out of that system. The present systemwould compete with current systems including a foam tape as used byother HVAC manufactures.

In one configuration, the paint sealant 50 is a rubberized paintproduct. Generally, this configuration of the paint sealant 50 isselected to create a seal, wherein the sealant can be color coated orcoded to distinguish its specific application, and properties, andintent, so that the consumer could easily identify its specific use andapplication.

The paint sealant 50 is not a traditional mastic or cellular foam.

In a further configuration, the paint sealant 50 is applied into thelocks or seams of black woodstove pipe. This application of the paintsealant 50 represents a novel construction of high temperature blackstove pipe and fittings.

In those configurations where the paint sealant 50 is to be cured,depending on the cure mechanism a hot blower or infrared light can bepositioned along the processing line downstream of the paint sealantapplication.

Thus, the paint sealant 50 forms a substantially solid, non-cellularstructure which resides at the confronting surfaces without interferingwith the assembly of the component in the assembled configuration. Thepaint sealant 50 provides a sufficient compression to accommodatetolerances in the confronting surfaces.

Although the paint sealant 50 has been set forth in terms of a sheetmetal HVAC component, it is understood the paint sealant can be appliedto venting or duct products that are coated in ceramic or painted asknown in the art. Premium decorative high end venting and duct work isoften painted or coated in ceramic or traditional paint products so asto provide designer finishes. However, these finishes do not address theleakage and seam sealing issues. In addition, to the sheet metalcomponents, the paint sealant 50 can be employed with venting or ductproducts constructed of a variety of other materials including, but notlimited to steel, galvanized steel, galvanized mild steel, aluminum, oralloy of these.

The present disclosure has been described in detail with particularreference to a presently preferred embodiment, but it will be understoodthat variations and modifications can be effected within the spirit andscope of the invention. The presently disclosed embodiments aretherefore considered in all respects to be illustrative and notrestrictive. The scope of the invention is indicated by the appendedclaims, and all changes that come within the meaning and range ofequivalents thereof are intended to be embraced therein.

The invention claimed is:
 1. A metal duct component comprising: a. a first surface and a second surface movable between an unassembled position and an assembled position; and b. a paint sealant on each of the first and the second surfaces, the paint sealant having a substantially planar surface and being one of dried or cured, wherein the substantially planar surface of the paint sealant on the first surface overlaps the planar surface of the paint sealant on the second surface in the assembled position.
 2. The metal duct component of claim 1, wherein the paint sealant is rubberized.
 3. The metal duct component of claim 1 wherein the paint sealant includes a thermoplastic, a thermoplastic elastomer or a thermoset.
 4. The metal duct component of claim 1, wherein the paint sealant includes an elastomer.
 5. The metal duct component of claim 1, wherein the paint sealant has a combined thickness between 2 mils and 125 mils.
 6. The metal duct component of claim 1, wherein the paint sealant is an elastomeric paint.
 7. A metal duct component comprising: a. a paint sealant on a portion of the metal duct component, the paint sealant having a substantially planar surface and being one of dried or cured, said sealant having a thickness between 2 mils and 125 mils.
 8. The metal duct component of claim 7, wherein the paint sealant is rubberized.
 9. The metal duct component of claim 7, wherein the paint sealant comprises a first substantially planar paint sealant layer on a male portion of the duct component and a second substantially planar paint sealant layer on a female portion of the duct component.
 10. The metal duct component of claim 7, wherein the duct component is moveable between an assembled position and an unassembled position, and wherein the first substantially planar paint sealant layer on the male portion overlaps the second substantially planar paint sealant layer on the female portion in the assembled position.
 11. A metal duct component comprising: a. a male portion having a paint sealant on a first surface; and b. a female portion having a paint sealant on a second surface, wherein the male portion and the female portion are moveable between an unassembled position and an assembled position, and wherein the paint sealant on the second surface overlaps the paint sealant on the first surface in an assembled position and has a thickness between 2 mils and 125 mils. 